The aim of this Action is to design multifunctional, light and compact noise reducing treatments. In order to achieve this, DENORMS will bring together skills and knowledge of the complementary, but still disconnected, communities of EU scientists working on acoustic metamaterials, sonic crystals and conventional acoustic materials. This Action will provide a framework for an efficient information exchange, help to avoid duplication of research efforts and channel the work of groups involved in different projects towards the common goal. New approaches to the theory of sound interaction with materials and structures and standard methods of their performance characterisation will be developed. The participation of EU companies in the network will facilitate the knowledge transfer from the academia to industry.